title: The tubulin cofactor C family member TBCCD1 orchestrates cytoskeletal filament formation.
abstract: TBCCD1 is an enigmatic member of the tubulin-binding cofactor C (TBCC) family of proteins required for mother-daughter centriole linkage in the green alga Chlamydomonas reinhardtii and nucleus-centrosome-Golgi linkage in mammalian cells. Loss of these linkages has severe morphogenetic consequences, but the mechanism(s) through which TBCCD1 contributes to cell organisation is unknown. In the African sleeping sickness parasite Trypanosoma brucei a microtubule-dominant cytoskeleton dictates cell shape, influencing strongly the positioning and inheritance patterns of key intracellular organelles. Here, we show the trypanosome orthologue of TBCCD1 is found at multiple locations: centrioles, the centriole-associated Golgi 'bi-lobe', and the anterior end of the cell body. Loss of Trypanosoma brucei TBCCD1 results in disorganisation of the structurally complex bi-lobe architecture and loss of centriole linkage to the single unit-copy mitochondrial genome (or kinetoplast) of the parasite. We therefore identify TBCCD1 as an essential protein associated with at least two filament-based structures in the trypanosome cytoskeleton. The last common ancestor of trypanosomes, animals and green algae was arguably the last common ancestor of all eukaryotes. On the basis of our observations, and interpretation of published data, we argue for an unexpected co-option of the TBCC domain for an essential non-tubulin-related function at an early point during evolution of the eukaryotic cytoskeleton.
authors.affiliation: Faculty of Health and Medicine, Division of Biomedical and Life Sciences, Lancaster University, Lancaster LA1 4YQ, UK.
authors.forename: Jane
authors.initials: J
authors.lastname: André
authors.forename: Stephanie
authors.initials: S
authors.lastname: Harrison
authors.forename: Katie
authors.initials: K
authors.lastname: Towers
authors.forename: Xin
authors.initials: X
authors.lastname: Qi
authors.forename: Sue
authors.initials: S
authors.lastname: Vaughan
authors.forename: Paul G
authors.initials: PG
authors.lastname: McKean
authors.forename: Michael L
authors.initials: ML
authors.lastname: Ginger
mesh_terms: D000818:Animals; D002502:Centrioles / Q000378:metabolism / Q000648:ultrastructure; D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D019143:Evolution, Molecular; D006056:Golgi Apparatus / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D008928:Mitochondria / Q000378:metabolism / Q000648:ultrastructure; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D014346:Trypanosoma brucei brucei / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D018832:Molecular Chaperones; D015800:Protozoan Proteins; C455270:tubulin-specific chaperone C
keywords: Cytoskeleton; Golgi; Kinetoplast; TBCC domain; TBCCD1; Trypanosome; Tubulin-binding cofactor C